From Sahih Muslim (Hadith 5757):
Asma' reported that a woman running high fever was brought to her. She asked water to be brought and then sprinkled it in the opening of a shirt at the uppermost part of the chest and said that Allah's Messenger (ﷺ) had said:Cool (the fever) with water. for it is because of the vehemence of the beat of Hell
Reference: Muslim 5757